A kind of method obtaining sulphur from Coal Chemical Industry and power plant's sulfur compound
Technical field
The present invention relates to a kind of method extracting sulphur, particularly a kind of method obtaining sulphur from Coal Chemical Industry and power plant's sulfur compound.
Background technology
Coal Chemical Industry refers to coal to be that raw material changes into gas, liquid and solid through chemical process and is processed into the commercial run of a series of Chemicals further.The operation of coal chemical engineering equipment must rely on huge electric power energy consumption, thus in Coal Chemical Industry process of construction often enterprise need invest and establish power plant for self-supply.
In gasification hydrogasification process, element sulphur contained in coal and hydrogen generate hydrogen sulfide, gasification gas need could synthesize number of chemical product after desulfurization and decarburization, existing desulfurization and decarburization is a kind of method of physics, the such as technology such as low-temperature rectisol, NHD, MDEA absorption, hydrogen sulfide and carbonic acid gas dissolve in the solution under specified conditions (temperature, pressure etc.), under environment (temperature, pressure etc.) change, hydrogen sulfide flashes off, and this portion gas needs qualified discharge after treatment.
Power plant for self-supply adopts coal firing boiler generating, and the element sulphur contained in coal is oxidized to sulfurous gas in combustion.The technique of mainly " limestone-gypsum method " or " ammonia process of desulfurization " of the existing employing of the improvement for sulfurous gas, this technology uses extensively, but processing efficiency is not high, and regenerant is worth not high, can produce secondary pollution.
At present, coal chemical industry enterprises adopts two to overlap independently device process to two kinds of dusty gass that this produces, add the gross investment of project, the sulfur-bearing total amount of power plant is larger, cause reclaiming product economic worth lower, total emission volumn still keeps high-order, from environmental protection and recycling economy angle, does not well embody.
Summary of the invention
Technical problem to be solved by this invention is to overcome the defect existed in above-mentioned prior art, and provides a kind of method obtaining sulphur from Coal Chemical Industry and power plant's sulfur compound of the unified improvement of the sulfide of applicable coal chemical industry enterprises gasification and coal-fired boiler in power plant and recycling.
For solving the problems of the technologies described above, the method obtaining sulphur from Coal Chemical Industry and power plant's sulfur compound comprises the following steps:
(1) coal-burning boiler system flue gas out carries out concentration after carrying out dedusting, improves the content of sulfur dioxide in flue gas.
(2) flue gas through concentration enters constant temperature Chemoselective reduction device after smoke-gas preheater heating, and utilize additional hydrogen as reductive agent, under selective reduction catalyst effect, react generation elemental sulfur, and chemical equation is:
H
2+SO
2=S+H
2O ①
React the heat produced to be taken away by the spiral coil cooling tube be arranged in described constant temperature Chemoselective reduction device, make temperature in described constant temperature Chemoselective reduction device maintain about 210-24O DEG C.
(3) after the flue gas of catalytic reduction deviates from molten sulfur by sulfur condenser, enter claus reaction device, wherein said molten sulfur enters molten sulfur pond.
(4) sulphur contained in the tail gas of claus reaction device and sulfide change into sulfurous gas after incinerator burns, deliver to boiler systems to mix with the Process Gas after dedusting, carry out concentration, the gas discharged in concentration process is mainly carbonic acid gas, component in former boiler smoke is mainly made up of carbonic acid gas and sulfurous gas, and the amount reducing carbonic acid gas makes sulfur dioxide concentration in gas assemble by concentration process.
In described step (3), enter the gasification sour gas also comprised through preheating of described claus reaction device, described sour gas enters described claus reaction device after acid gas separating tank carries out entering the heating of acid gas preheater after gas delivery.
Described claus reaction device comprises one-level claus reaction device, secondary claus reaction device, one-level sulfur condenser, secondary sulfur condenser and secondary reheater; Described firsts and seconds claus reaction device is in-built fills out high-efficiency activated catalyzer, first the described flue gas through catalytic reduction enters one-level claus reaction device and carries out catalyzed reaction, then one-level sulfur condenser is entered, the molten sulfur deviate from enters molten sulfur pond and flue gas enters secondary claus reaction device continuation catalyzed reaction, flue gas through quadric catalysis reaction enters secondary reheater and then enters secondary sulfur condenser, and the molten sulfur deviate from through condensation process enters molten sulfur pond.
The amount of reductive agent hydrogen is added by the H being arranged on claus reaction device in described step 2
2s/SO
21. ratio Analysis instrument determines according to reaction equation, namely enters the H of claus reaction apparatus
2s/SO
2ratio is as being greater than 2, then the amount reducing hydrogen makes H
2s/SO
2ratio trend towards 2; As being less than 2, then the amount increasing hydrogen makes H
2s/SO
2ratio trend towards 2.
Carry out the gas of concentration in described step 4 after deoxidation reactor deoxidation, react with the absorption cycle liquid of Trisodium Citrate in tail gas absorber:
SO
2(gas) → SO
2(liquid)
SO
2(liquid)+H
2o → H
++ HSO
3 -
Cit
3-+H
+→HCit
2 -
HCit
2-+H
+→H
2Cit
-
H
2Cit-+H
+→H
3Cit
3SO
2+3H
2O+Na
3Cit→3NaHSO
3+H
3Cit
Be mainly carbonic acid gas by above reaction end gas absorption tower expellant gas and reach effluent standard.
The method obtaining sulphur from Coal Chemical Industry and power plant's sulfur compound provided by the invention changes the construction mode that treatment system is overlapped in boiler desulfurization system and gasification sulfur recovery two, substantial saving in investment, any sour gas concentration of hydrogen sulfide can be met, the load variations of sulfur dioxide in flue gas concentration, changing sulfur recovery Cross unit because of concentration of hydrogen sulfide change cannot drive phenomenon, sulphur recovery efficiency is high, can more than 99.9% be reached, highly purified sulphur can be obtained, produce huge recycling economy to be worth, avoid desulphurization system because of sulfur dioxide corrosion phenomenon, and waste gas is better than national standard discharge, really realize energy-saving and emission-reduction, waste water is not produced in treatment process, there is no secondary pollution, and floor space of the present invention is little, construction cost is cheap, run simple, convenient operation and management, working cost is low, steam is self-produced personal.In view of the needs of China's modernization construction, this invention has wide market outlook, and its release must bring good economic benefit and social benefit.
Accompanying drawing illustrates:
Fig. 1 is the method flow schematic diagram obtaining sulphur from Coal Chemical Industry and power plant's sulfur compound;
Fig. 2 is claus reaction apparatus structure schematic diagram.
Embodiment:
Below in conjunction with accompanying drawing, inventive embodiment is described in further detail.
Embodiment 1: as shown in Figure 1, the present invention includes following steps:
(1) coal-burning boiler system flue gas out enters concentrating unit 2 and carries out concentration after cleaning apparatus 1, improves the content of sulfur dioxide in flue gas.
(2) flue gas through concentration enters constant temperature Chemoselective reduction device 4 after smoke-gas preheater 3 heats, utilize additional hydrogen as reductive agent, under selective reduction catalyst effect, react generation elemental sulfur, and chemical equation is:
H
2+SO
2=S+H
2O ①
The heat reacting the steam of the 2.1-2.6MPaG produced is taken away by the spiral coil cooling tube being arranged on described constant temperature Chemoselective reduction device 4, makes described constant temperature Chemoselective reduction device 4 temperature maintain about 230 DEG C.
(3) deviate from molten sulfur through the flue gas of catalytic reduction by sulfur condenser 5 and produce the steam of 0.3-0.5MPaG, then add after the steam of 3.82MPaG or middle pressure steam through one-level reheater 6 and enter claus reaction device 7, wherein said molten sulfur enters molten sulfur pond 8.
(4) sulphur contained in the tail gas of claus reaction device 7 and sulfide change into sulfurous gas after incinerator 9 burns, deliver to boiler systems to mix with the Process Gas after dedusting, carry out concentration, the gas discharged in concentration process is mainly carbonic acid gas, and produces steam or the middle pressure steam of 3.82MPaG.
Embodiment 2: difference from Example 1 is:
In described step (3), enter the gasification sour gas also comprised through preheating of described claus reaction device 7, described sour gas enters after acid gas preheater 11 heats and enters described claus reaction device 7 after acid gas separating tank 10 carries out gas delivery.
Embodiment 3: difference from Example 1 is:
Described claus reaction device 7 comprises one-level claus reaction device 12, secondary claus reaction device 13, one-level sulfur condenser 14, secondary sulfur condenser 15 and secondary reheater 16; Described one-level claus reaction device 12 and secondary claus reaction device 13 is in-built fills out high-efficiency activated catalyzer, first the described flue gas through catalytic reduction enters one-level claus reaction device 12 and carries out catalyzed reaction, then one-level sulfur condenser 14 is entered, the molten sulfur deviate from enters molten sulfur pond and flue gas enters secondary claus reaction device 13 continues catalyzed reaction, flue gas through quadric catalysis reaction enters secondary reheater 16 and then enters secondary sulfur condenser 15, and the molten sulfur deviate from through condensation process enters molten sulfur pond 8.
Embodiment 4: difference from Example 1 is:
The amount of reductive agent hydrogen is added by the H being arranged on claus reaction device 7 in described step 2
2s/SO
21. ratio Analysis instrument 17 determines according to reaction equation, and namely enter the H2S/SO2 ratio of claus reaction apparatus 7 as being greater than 2, then the amount reducing hydrogen makes H
2s/SO
2ratio trend towards 2; As being less than 2, then the amount increasing hydrogen makes H
2s/SO
2ratio trend towards 2.
Above embodiments of the invention have been described in detail, but described content being only preferred embodiment of the present invention, can not being considered to for limiting practical range of the present invention.All equalizations done according to the present patent application scope change and improve, and all should still belong within patent covering scope of the present invention.